Multiplying machine



\ VENTOR .ATTORNEY Dec. 8, 1942- .1. M. CUNNINGHAM MULTIPLYING MACHINE Filed May 17, 1941 8 Sheets-Sheet 1 9 J. M. CUNNINGHAM 2,304,495

MULTIPLYING MACHINE ATTORNEY 8, 1942. J. M. CUNNINGHAM uuunrume men-nus aged lay 1'7. 1941 8 Sheets-Sheet 3 ATTORNEY Dec. 8, 1942; CUNNINGHAM 2,304,495

MULTIPLYING MACHINE Filed May 17, 1941 8 Sheets-She 4 Q Q 3 \Q ATTORNEY 1942- J. M. CUNNINGHAM 9 MULT IPLY ING MACHINE Fi led May 17, 1941 8 Sheets-Sheet 5 mn somQmm -b INVENTOR BY i A TTORNE Y Dec. 8, 1942. J. M. CUNNINGHAM 2,304,495

HULTIPLYING MACHINE Filed llay 17, 1941 8 Sheets-Sheet 6 A TTORNEY 8, 1942. J. M. CUNNINGHAM MULTIPLYING MACHINE Filed May 17, 1941 8 Sheets-Shea} 7 A TTORNEY Dec. 8, 1942- .1. M. cuNnmer-mm 2.

MULTIPLYING MACHINE Filed May 17, 1941 8 Sheets-Sheet 8 FIGA.

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MULTIPLYING MACHINE James M. Cunningham, Endicott, N. Y., asslgnor to International Business Machines Corporation, New York, N. Y., a corporation of New York Application May 17, 1941, Serial No. 393,872

(Cl. 2356l.6i

2 Claims.

This invention relates to accounting machines and more particularly to multiplying machines of the general class in which multiplication is effected by the formation of multiples of the multiplicand and the combining of the formed multiples to obtain the product.

In effecting multiplying, four accumulators are employed each related to one of the digits 5, 4, 2 and l. The accumulator related to the digit is provided with a so-called "times 5" readout, whereby five times the amount standing therein may be read out. The accumulators related to the 4 and 2 digits each have a so-called "times 2" readout. whereby twice the amount standing therein may be read out.

Multiplying is effected separately for each digit of the multiplier, which digits are inspected and devices controlled thereby to cause the multiplicand to be entered in one or two of the four accumulators whose related digit or the sum of whose related digits equals the multiplier digit. When all multiplier digits have been acted upon. the amount in the accumulator related to the 5 digit is transferred to the accumulator related to the 1 digit, and concurrently therewith the amount in the accumulator related to the 4 digit is transferred to the accumulator related to the 2 digit. Following this, the amount in the accumulator related to the 2 digit is transferred to the accumulator related to the 1 digit. This results in the formation in the accumulator related to the 1 digit of the complete product.

Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of example, the principl of the invention and the best mode, which has been contemplated. of applying that principle.

Figs. 1 and la taken together show a somewhat diagrammatic view of the various mechanical units of the machine and also the driving mechanism for the various units.

Figs. 2, 2a, 2b and 2c taken together and arranged vertically in the order named show the complete circuit diagram of the machine.

Figs. 3 and 3a taken together show the timing diagram of the machine.

Fig. 4 is a diagram showing the several steps involved in the multiplication of two factors.

The mechanical structure of the machine is substantially the same as that shown in Patent 2,045,437, granted to G. F. Daly on June 23, 1936. This patent shows a multiplying machine controlled by record cards upon which multiplier and 'multiplicand factors are punched. These cards are handled one by one and the factors sensed therefrom and entered into accumulators or entry receiving devices. In the present machine, the multiplier and multiplicand factors are derived from record cards in exactly the same manner. so that the mechanism for feeding cards and entering a pair of factors of each into entry receiving devices will be but briefly described.

In the machine of the Daly patent, the two factors are multiplied by what is known as the "partial products" method of multiplication, and the product is obtained in a "products" accumulator. The present invention is concerned with a different method and mechanism for obtaining the product and this will be explained in detail. After the product is obtained in the product accumulator, it is punched back on the record card from which the factors were derived. The mechanism for punching back the product is the same as in the patent so this mechanism too will be but briefly explained herein. In the drawings the reference characters employed are those applied to corresponding parts in the patent, so that the same may be readily referred to for more detailed explanation.

Macrame Darva Referring to Fig. l. the machine is driven by motor Z which through a belt and pulley drive connection drives a shaft 5i and generator 52. Through gearing 53 a vertical shaft 5! is driven which in turn through gears 55 and 55b drives shafts 56 and 55b, respectively. The accumulators are driven from these shafts in the customary manner. For present purposes, six accumulators are required which are designated in Fig. l as MC, MP, A, B, C, and D. Each accumulator is also provided with the usual reset drive which, for the upper shaft, involves gearing 51, 58 and Geneva drive 50, iii, 62 to the reset shaft 63. The lower shaft 53b is driven in a similar manner from shaft 55b. From the shafts 53 and 631: the accumulators are reset in the customary manner by eiectromagnetically controlled one-revolution clutches whose controlling magnets are generally designated 392 in Fig. l.

CARD Far-m AND Caan HANDLING UNIT In Fig. 1a, the shaft 56 through gearing 68|3 drives a one-revolution clutch element 16 of a one-revolution clutch which is controlled by the magnet 384 in the usual manner. When the magnet is energized, the record cards are fed from a stack of cards I05 by a picker I04 through feed rollers 82, and thence between rollers 94 and contact roller 81, thence over rollers '95 to a position designated R in the punching section of the machine. This card feed mechanism is the same as in the patent referred to.

In the lower part oi Fig. la, the shaft 56b actuates parts in the MP8, CS and CR units which are the usual magnetically tripped and mechanically operated multicontact relay devices operated by the cams 65 and connections 68, 81.

Cmcur'r DIAGRAM With the above brief explanation of the mechanical units, the operation of the device may best be explained in connection with the circuit diagram. As usual, in setting the machine into operation, prepunched cards are placed in the card magazine and the first operation is to close the main line switch (not shown) which provides current for the driving motor Z. The motor drives generator 52, the D. C. section of which supplies direct current to the D. C. lines "i and 382. Alternating current impulses are supplied to ground and to bus 283 (see Fig. 2). The start key is now depressed to close start key contacts 215 (Fig. 2c) and to complete a circuit from the SGI side of the D. C. line through relay magnet C, start key contacts 215, relay contacts GI now closed, cam contacts FC2 to the "2 side of the D. C. line. A stick circuit is established through the contacts C2 of the magnet C and cam contacts FC8 now closed. Energization of magnet C also closes contacts Cl and a circuit is established, traced as follows: From line IBI, through relay contacts Fl which are now in the position shown, card feed clutch magnet 384 (see also Fig. 1a), cam contacts FCG, stop key contacts 215, contacts Ni and Cl now closed, punch control contacts Pi to line 382.

The start key is held depressed for the first four machine cycles in starting up upon the run of cards. The starting is prevented until the feed-rack IBI (see Patent 2,045,437, Fig. a.) of the punch is in its right hand position. This is provided for by contacts Pi. The first complete card feed cycle upon starting of the machine will advance the first card to a point where the 9 index point position of the card will be about ready to pass under the sensing brushes ")9. At the beginning oi the second card feed cycle, the card traverses the sensing brushes Hi9, and the multiplier and multiplicand are read from the card and entered into the MP and MC receiving devices. At the end of the first card feeding cycle, the card lever contacts H2 (Fig. 20) will be closed by the card, causing energization of relay magnet H, and cause relay contacts HI (Fig. 2) to shift from the position shown to reverse position. As the second card feed cycle ensues, the card is carried past the sensing brushes and amounts are entered into the multiplicand and multiplier devices.

The factor entry circuits will now be traced. Current flows from the A. C. line 283 (Fig. 2). through relay contacts Hi now shifted, cam contacts FCI. which close at the proper time in the cycle (see Fig. 3), through the impulse distributor 259, to card transfer and contact roll 81. thence through the brushes Hi9 pertaining to the multiplier (these being designated IBQMP on Fig. 2) and in parallel through the brushes iilSMC pertaining to the multiplicand to plug sockets. The customary plug connections are provided and connected to the plug sockets associated with the accumulator magnets designated HUMP and 35llMC, so that the entry circuit extends to the multiplier and multiplicand adding magnets. For normal multiplying operations, switch 39! is in closed position as shown. The ground return circuit for the magnets 29(IMC and 39iiMP is through the closed relay contacts A2 which are in the position shown. After the card passes the sensing brushes, it is fed to the card handling section of the machine and ultimately passes to the R position (Fig. 1a) of the punch, closing card lever and contacts I20 (Fig. 2c) and energizing relay magnet F, causing the shifting of relay contacts Fl to reverse position from that shown.

In starting up the machine the punch racks are in extreme outer position so that contacts PI, P3, P4 and P5 are closed. With contacts P5 closed, relay magnet K will be energized and its contacts Ki shifted to reverse position from that shown. Upon the shifting of relay contacts Fi and upon the closure of cam contacts CC3 (Fig. 20), a circuit will be established to the punch clutch magnet i whose energization will cause closure of a pair of contacts (I91 of the Daiy patent). These contacts, as usual, supply current to the driving motor of the punch so that the card is advanced endwise in the punch to the position in which punching is to commence.

Up to this point, the operation of the machine is substantially the same as that of the Daiy patent, that is, the cards are handled, and the multiplier and multiplicand factors are entered into the MP and MC devices in the same manner. According to the present invention, the actual multiplying operation and the setup of the cycle controller is initiated by the reset of the C accumulator. Such reset of the C accumulator is initiated and effected in the following manner.

It has been previously explained how relay magnets F and K are energized. Energization of these two magnets closes contacts F2 and K2 (Fig. 2). Upon closure of cam contacts 0C2, current flows from line "3, contact CC2, contacts K2, normally closed contacts L2, contacts F2 to reset magnets "20 and 392D of accumulators C and D respectively, thence to ground. Energization of these magnets initiates the resetting of their respective accumulators (see Fig. 1).

During the reset of the C accumulator, the reset contacts 212 (Figs. 1 and 20) close and a circuit is established to relay magnet L, energizing this magnet and causing the opening of relay contacts L2 (Fig. 2) to prevent a repetition of the reset of the C and D accumulators. The machine is now ready to set up the cycle controller and follow with the actual multiplying operations.

The operation of the cycle controller in the present case is Just as in the Patent 2,045,437. Upon reset of the C accumulator, a circuit is established from line 382 (Fig. 2), reset contacts 210 which become closed upon the reset of the C accumulator, through relay magnets M and N, back to the other side of line "I. The energization of relay magnet M will close contacts MI and M2 oi which the latter establishes a holding circuit for the magnets M and N through a wire (I (Figs. 2a, 2b, 20), through the new closed reset contacts 2'" of the multiplicand accumulator MC (see Fig. l).

COLUMN SKIP AND CYCLE CONTROLLER The cycle controller elements are shown in Fig. 2 where the same reference characters are used as in the patent referred to, and the multiplier readout device with which they are asso- Search H:

elated is limited to four orders. If any brush of the multiplier readout stands upon the related zero spot, its corresponding Y magnet would be energized, the current flowing from D. C. line 382 to reset contacts 314, wire ll, relay contacts M2 (now closed) over wire 392 to the zero spots of the MP readout device, thence through the corresponding brush or brushes extending on the zero spot or spots, then through the circuits shown to the respective Y magnets and back to the SM side of the D. C. line. When any Y magnet becomes energized due to a brush standing on a zero spot in its corresponding column, the energization of this particular Y magnet will close its corresponding Yi holding contacts and the Y magnet will remain energized through a wire 393.

For the purposes of explanation. it will be assumed that significant digits are present in all four orders of the multiplier. The manner in which multiplying is carried out in the present invention will now be specifically explained, it being understood that the operation of the machine up to this point is substantially the same as explained in greater detail in the patent referred to.

METHOD OF MULTIPLICATION The manner in which multiplying is carried out may best be explained in connection with Fig. 4 which indicates that four accumulators designated A, B, C and D are utilized. Accumulator A is provided with what may be termed a times 5" readout so arranged and constructed that, when a reading is taken from such an accumulator, it will have a value 5 times the setting of the accumulator proper. The accumulators B and C are both provided with what may be termed a times 2" readout device, that is, when a reading is taken from either of these accumulators, its value will be twice the amount standing in the accumulator proper. The accumulator D is provided with the usual readout device for controlling the punching mechanism in the same manner as the usual LH accumulator of the prior patent. In carrying out multiplying, the multiplicand amount is transferred from the MC accumulator to accumulators A, B. C or D or combinations of these accumulators, in accordance with the values of the multiplier digits, each multiplier digit being handled separately. The selection of which of the four accumulators is to receive the multiplicand is made in accordance with the following table.

11 A and I).

7 and f. R. JLfami ii. 11.. A and B.

Thus, when the multiplier digit is 1, the multiplicand amount is transferred into accumulator D. When the digit is 2, it is transferred into accumulator C. When the digit is 3, the multiplicand is transferred into accumulators C and B, etc. Fig. 4 shows a problem involving a multiplicand of 7654 and a multiplier of 8639. As indicated on the first line designated "1st cycle," multiplication by 9 in accordance with the table involves the transfer of the MC amount to accumulators A and B. Since this is the units digit, the entry is made with the multiplicand in the position farthest to the right in these accumulators. The next digit of the multiplier is 3 which calls for the entry of the MC into the accumulators C and D. As this is a tens digit, the column shift will effect entry in these accumulators one place to the left as indicated on the line designated 2nd cycle" (Fig. 4). The third multiplier digit in this case calls for transfer into the A and D accumulators according to the table with appropriate column shift, so that the entry is made as indicated on the line designated "3rd cycle." For the digit 8 as indicated on the line designated "4th cycle," the multiplicand is entered in accumulators A, C and D with appropriate column shift. After each of the cycles, the amounts standing in these accumulators are as indicated on the lines designated "Totals."

Following the four transfer cycles, one for each of the multiplier digits, the machine will enter upon two transfer or gathering cycles, during the first of which the amount in accumulator A is transferred by means of its times 5 readout to accumulator D. Concurrently therewith, the amount in accumulator B through its times 2 readout is transferred to accumulator C, resulting in the totals therein as indicated. During the second transfer cycle, the amount in accumulator C is transferred through its times 2 readout to accumulator D, resulting in the final product 66122906.

Examination of the procedure involved will show that the accumulators A, B, C and D are allocated to the digits 5, 4, 2, 1, respectively, and that entry of the multiplicand into these four accumulators is in accordance with the accumulator whose digit corresponds to the multiplier digit or the accumulators the sum of whose related digits corresponds to a multiplier digit. It is to be noted in the final two transfer cycles that the entries in accumulator A, which is related to the 5 digit, are in effect multiplied by 5 by reason of the times 5 readout. The entries in accumulator B related to the digit 4 are in effect multiplied by 4 by reason of the double transfer of the total in this accumulator, that is, from accumulator B to C and then again from C to D which is a double transfer, each transfer being through a times 2 readout.

Referring now to Fig. 2, initiation of multiplication is effected in the following manner. Upon the energization of relay magnet M, the contacts Ml close. Following the setup of the cycle controller, cam contacts CCZ close, permitting current to flow from line 383, through the cam contacts, relay contacts HI now closed, through contacts Yul, down through column shift relay magnet CSu, out through the brush which is standing on the 9 spot of the readout in the units order for the example chosen in Fig. 4. thence through the related wire 394, to the X9 multiplying control magnet to ground. Energization of the column shift magnet CSu controls the direction of the transfers, while the magnet X9 determines that the amount standing in the MC accumulator is to be transferred to accumulators A and B.

This determination is effected as follows. In Fig. 20, each of the multiplying control magnets Xl to X9 causes the closure of a related set of contacts identified by the suffix a, all of which are connected to line 882 and selectively to one or more of a set of four multicontact relays designated AR, BR, CR, and DR. The prefixes A, B, C and D of these relays indicate the transfers which they control, and the wiring connections between the contacts of the multiplying control magnets and these multicontact relays are in accordance with table hereinabove. Thus, it will be observed that with magnet x9 energized, the relay magnets AR and BB. will be energized through cam contacts CCI which maintain the magnets energized during the entering portion of the cycle (see Fig. 3). The contacts of these relays AR, BR, CR and DR are shown in Fig. 2a where they are designated by the suffix a. The readout device oi the multiplicand accumulator MC is connected through wires 500, contacts controlled by the column shift magnets, a group of wires Bill, to the contacts ARa, etc. to the adding magnets generally designated 390 of the four accumulators A, B, C and D.

Emitter 255 will send impulses from AC, line 382, through the MCR readout device in accordance with the multiplicand standing therein, to the appropriate accumulators, with the CS devices determining the denominational position in which the entries are to be made, and the magnets AR, etc. determining which accumulators are to receive the entry or entries. Through the operation of the cycle controller in the same manner as in the Daly patent. the multiplying control magnets XI to K9 are energized one in each of the multiplying cycles in accordance with the value of the multiplier, so that for the capacity shown, four multiplying cycles take place in succession, during which the magnets X9, X3, X8 and K8 are energized in succession to control the entries into the four accumulators in the manner represented in Fig. 4.

There follow now the two cycles which may be called the "gathering" cycles, and these are initiated as follows. When entries have been effected under control of all the multiplier digits, a circuit will be completed when cam contacts CO2 close, traceable from line 383, contacts C02, Mi, all the left hand contacts Yu2, Yt2, Yh2, Yth2 (which are now closed) to energize relay magnet ICR and reset magnet 392MC. The circuit also extends through cam contacts FCIU to energize reset magnet 2MP. The energization oi the last two magnets will cause resetting of the multiplier and multiplicand amounts in the usual manner.

Energization of relay magnet ICR closes two sets of contacts designated iCRa, ICRb (Fig. 2a), the former of which are connected through a group of wires 502 to the entering magnets 390D of accumulator D, and the latter are connected through a group of wires 503 to the entering magnets 3900 of accumulator C. Contacts lCRa are also connected to the readout designated BMCRO oi accumulator A, while contacts lCRb are wired through readout device designated lMCRO of accumulator B. With these contacts closed, emitter 255 (Fig. 2a) will transmit impulses through a group of wires designated M (Figs. 2a and 21:), through the devices SMCRO and IMCRO to enter the amount standing in accumulator A at 5 times its value into accumulator D and the amount standing in accumulator B at twice its value into accumulator C. The specific arrangement of the times 5 and the times 2 readout devices will be explained later.

During the cycle in which these amounts are transferred, relay contacts iCRc closed by the magnet ICR will complete a circuit (Fig. 2c) from line 382, contacts iCRc, relay magnet D, line 3M. Contacts D2 provide a holding circuit through contacts CCI. The second pair of contacts DI (Fig. 2) upon closure complete a circuit from line 383, contacts 0C2, Di, and a magnet 203 in parallel with reset magnets 292A and 29213.

In Fig. 2b, the magnet 20R closes a group of contacts 2cm which connect the readout device 2MCRO of accumulator C, through a group of wires 505 (Fig. 2a) to the adding magnets 350D of accumulator D, so that during the cycle impulses from emitter 285 will flow through wires 50! (Fig, 2b), through the readout device of accumulator C and to the magnets of accumulator D.

The manner of wiring a readout device such as SMCRO associated with accumulator A is well known and is shown in Patent 2,192,729 granted March 5, 1940, to A. H. Dickinson. Sufllce it to say that the usual commutator spots and segments are wired so that, with the connecting brushes in position to represent any amount, impulses from emitter 265 through wires 504 will be directed to the group of wires 502 to represent 5 times the amount standing in the accumulator. The readout devices for accumulator B and accumulator C are wired in the well known manner to control the reading out of 2 times the amount standing in the accumulator. Such readout devices are also shown in the Dickinson patent referred to, so that they need not be spe cifically described herein, except to state generally that the wiring connections between the commutator segments and the common strips are such that, with the readout brushes standing in position to represent any amount, impulses from the emitter will be directed through the readout devices, so as to represent twice the amount standing in the accumulator. The 2 times readout is also shown in Patent 2,166,928, granted to J. W, Bryce on July 25, 1939.

As mentioned, the MC and MP accumulators reset concurrently with the transfer operation from accumulators A and B to accumulators C and D. The resetting of the MC accumulator will cause the opening of contacts 214 (Fig. 2c) which breaks the holding circuit for magnets M and N and for all the Y magnets, thus preparing the cycle controller for a new entry from the following card. The reset of the multiplicand accumulator also brings about the closure of con tacts 214a. Closure of contacts 2140. brings about energization of relay magnet C which closes its contacts Cl, so that there is an energization of card feed clutch magnet 384.

As may be seen from Fig. 3a, the card feed cycle takes place while accumulators A and B are resetting, and while the amount in accumulator C is being transferred to accumulator D.

During the second half of the card feed cycle, cam contacts FC4 (Figs. 2c and 3a) close, energizing magnet B. closing holding contacts B2 and providing a holding circuit for magnet B through contacts 2' of accumulator C. Magnet B also closes its contacts Bi which initiate punching operations in the usual manner by supplying current from line 382 (Fig. 20), contacts Bi, 2H5, switch "5, wire 406 to conducting strip 222. As usual, current from strip 222 is directed through brushes 223 to segments 22l in succession, and these are plug-connected to the usual readout device of accumulator D (not shown) and the punch magnets (also not shown).

When the punching is completed the card carriage rack will escape to beyond the last column position and contacts P5 (Fig. 2c\ will close to energize magnet K, shifting contacts Kl to energize the card eject magnet 23 so that the punched card will be ejected.

A new multiplying operation will then be initiated upon the succeeding record card. Such succeeding operation is initiated by the closure of relay magnet contacts K! (Fig. 2) which complete a circuit from line 383, contacts C02, K2. L2 (now closed), F2 (also closed). to reset magnets 2920 and 2920 of the C and D accumulators. As a result. of the resetting of accumulator C, the related contacts 210 (Fig. 2) again set up the cycle controller circuits and energize magnets M and N. Also, opening of contacts 2' (Fig. 2e) breaks the holding circuit of magnet B and causes contacts Bl to open the punch operating circuits through the conducting strip 222.

While there has been shown and described and pointed out the fundamental novel features of the invention as applied to a single modification, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention. It is the intention therefore to be limited only as indicated by the scope of the following claims.

What is claimed is:

1. In a multiplying machine. a device settable to represent a multiplier. a device settable to represent a multiplicand, four accumulators, one for each of the digits 1, 2, 4 and 5, transferring means comprising denominational column shift instrumentalities between said multiplicand device and each of said accumulators for transferring the multiplicand from said multiplicand device to the accumulators. means controlled by said multiplier device, effective for each digit of the multiplier, for selectively rendering the transferring means effective to transfer the multiplicand to the accumulator whose related digit equals or the accumulators whose related digits when added equal the multiplier digit, a readout device for the accumulator related to the digit 5 Search Roon arranged to read out five times the amount thereon, a readout device for each of the accumulators related to the digits 4 and 2 arranged to read out two times the amount therein, means including the first named readout device for transferring the amount from the accumulator related to the 5 digit to the accumulator related to the 1 digit, means including the readout device of the accumulator related to the 4 digit for transferring the amount from the accumulator related to the 4 digit to the accumulator related to the 2 digit, means for rendering both said last named means effective after entries have been made from the multiplicand device, and means effective thereafter for transferring the amount from the accumulator related to the 2 digit to the accumulator related to the 1 digit whereby the latter accumulator will contain the product of the multiplier and multiplicand.

2. In a multiplying machine, a device settable to represent a multiplier, a device settable to represent a multiplicand, four accumulators, one for each of four different digits which singly or in combination represent the nine digits, transferring means comprising denominational column shift instrumentallties between said multiplicand device and each of said accumulators for transferring the multiplicand from said multiplicand device to the accumulators, means controlled by said multiplier device, effective for each digit of the multiplier, for selectively rendering the transferring means effective to transfer the multiplicand to the accumulator whose related digit equals or the accumulators whose related digits when added equal the multiplier digit, a readout device for each accumulator related to the three highest of said four digits each arranged to read out a predetermined multiple of the amount thereon, means for each of said readout devices for transferring the amount related to its accumulator to an accumulator related to a lower valued one of the four digits, means for rendering said readout transferring means effective after entries have been made from the multiplicand device, said separate readout transferring means being rendered effective in a predetermined order to ultimately obtain the combined accumulations in the accumulator related to the lowest of the four digits to represent the product of the multiplier and multiplicand.

JAMES M. CUNNINGHAM. 

